What are the options for a US citizen bringing a minor daughter to Thailand on a Non-B visa?

Can anyone tell me what the options are for me to bring my minor daughter with me when traveling on a non-immigrant B visa? Is there an option to get her a visa at the same time as mine or after mine is approved? She may be arriving a few weeks after me but will depart when I do. We are US citizens and will apply either at the Washington DC embassy or the New York City consulate. (I am still trying to determine if I may be required to use one particular one or if I can go to the one easiest for me to travel to.). I am a director and owner in a Thai company and my last business Visa was single entry issued in Hong Kong (only visa I've had though I have visited on tourist stamp before). I did take a weekend holiday to Vietnam shortly before leaving Thailand and had the proper re-entry permit. My daughter has 4 tourist visa entry stamps in her current passport. One for 2 weeks in 2017, one for 2 weeks in 2018 and two from 2019(30 days and then 5 days) - total number of days she's been in Thailand (lifetime) have been around 70- if any of that matters. She is 15 years old. Her previous visits were truly tourism although she did take a one month class in Thai language as well just "for fun". I worry more about her visa status than my own because she may be traveling alone (as she did without incident last summer). I don't want her to have any problems at immigration- she's a mature 15 and is well traveled but she's still only 15.